#coding:utf-8
#1_10_A 2015.4.10
import math

position = list(map(float,input().split()))
distance = math.sqrt((position[2] - position[0]) ** 2 + (position[3] - position[1]) ** 2)
print('{:.5f}'.format(distance)) import math math position = list(map(float,input().split())) position list(map(float,input().split())) list map(float,input().split()) map float input().split() ().split () input split distance = math.sqrt((position[2] - position[0]) ** 2 + (position[3] - position[1]) ** 2) distance math.sqrt((position[2] - position[0]) ** 2 + (position[3] - position[1]) ** 2) math.sqrt math sqrt (position[2] - position[0]) ** 2 + (position[3] - position[1]) ** 2 (position[2] - position[0]) ** 2 position[2] - position[0] position[2] position 2 position[0] position 0 2 (position[3] - position[1]) ** 2 position[3] - position[1] position[3] position 3 position[1] position 1 2 print('{:.5f}'.format(distance)) print '{:.5f}'.format(distance) '{:.5f}'.format '{:.5f}' format distance position = list(map(float,input().split())) list(map(float,input().split())) position distance = math.sqrt((position[2] - position[0]) ** 2 + (position[3] - position[1]) ** 2) math.sqrt((position[2] - position[0]) ** 2 + (position[3] - position[1]) ** 2) distance
#coding:utf-8
#1_10_A 2015.4.10
import math

position = list(map(float,input().split()))
distance = math.sqrt((position[2] - position[0]) ** 2 + (position[3] - position[1]) ** 2)
print('{:.5f}'.format(distance))